The present invention relates to an opening and closing apparatus for opening and closing a swingable member or apparatus, such as an automatic document feeder attached to a copying machine.
For use with electrophotographic copying machines or the like, such an automatic document feeder has been proposed which is disposed in an upper portion of the body of a copying machine, and when copies are made from sheet-like originals, the automatic document feeder is closed and the sheet-like originals are fed automatically, and when copies are made from a book or the like, the automatic document feeder is opened so that the book can be directly placed on a contact glass. Referring to FIG. 1, there is shown an example of such an automatic document feeder which is mounted on an upper portion of the body of a copying machine. When an original is inserted into an outlet portion 2 of the automatic document feeder 1, the original is transported onto a contact glass 6 by a sheet transport belt 5 trained over a pair of pulleys 3 and 4. The original is illuminated while it is stopped temporarily or moved continuously. The original is then discharged out of the automatic document feeder 1 through a pair of sheet discharge rollers 7. A base portion of the automatic document feeder 1 is pivotally attached to a shaft 10 of a support frame portion 8 of the body of the copying machine, so that the automatic document feeder 1 can be opened by being swung about the shaft 10. When copies are made from a book or the like, the automatic document feeder 1 is swung open as shown in FIG. 2, and the book is placed directly on the contact glass 6.
Since such an automatic document feeder includes an original sheet transportation mechanism and a drive motor and other devices, the automatic document feeder itself is typically heavy and substantial force is required to open the automatic document feeder so that it has a shortcoming of lacking for the highest safety in operation.